LIMA — In Peru, home to the spectacular Inca city of Machu Picchu and thousands of ancient
ruins, archaeologists are turning to drones to speed up sluggish survey work and protect sites from
squatters, builders and miners.

Remote-controlled aircraft were developed for military purposes and are a controversial tool in
U.S. anti-terrorism campaigns, but the technology’s falling price means it is increasingly used for
civilian and commercial projects around the world.

Small drones have been helping a growing number of researchers produce three-dimensional models
of Peruvian sites instead of the usual flat maps — and in days and weeks instead of months and
years.

Speed is an important ally to archaeologists here. Peru’s economy has grown at an average annual
clip of 6.5 percent over the past decade, and development pressures have surpassed looting as the
main threat to the country’s cultural treasures, according to the government.

Archaeologists say drones can help set boundaries to protect sites, watch over them and monitor
threats, and create a digital repository of ruins that can help build awareness and aid in the
reconstruction of any damage done.

“We see them as a vital tool for conservation,” said Ana Maria Hoyle, an archaeologist with the
Culture Ministry.

Hoyle said the government plans to buy several drones to use at different sites and that the
technology will help the ministry comply with a new, business-friendly law that has tightened the
deadline for determining whether land slated for development might contain cultural artifacts.

Drones already are saving archaeologists time in mapping sites — a crucial but often slow first
step before major excavation work can begin. Mapping typically involves tedious ground-level
observations.

“With this technology, I was able to do in a few days what had taken me years to do,” said Luis
Jaime Castillo, a Peruvian archaeologist with Lima’s Catholic University and an incoming deputy
culture minister who plans to use drones to help safeguard Peru’s archaeological heritage.

Castillo started using a drone two years ago to explore the San Jose de Moro site, an ancient
burial ground encompassing a little more than half a square mile in northwestern Peru, where the
discovery of several tombs of priestesses suggests that women ruled the coastal Moche
civilization.

“We have always wanted to have a bird’s-eye view of where we are working,” Castillo said.

In the past, researchers have rented crop dusters and strapped cameras to kites and
helium-filled balloons, but those methods can be expensive and clumsy. Now, they can build drones
small enough to hold with two hands for as little as $1,000.

“It’s like having a scalpel instead of a club; you can control it to a very fine degree,” said
Jeffrey Quilter, an archaeologist with Harvard University who has worked at San Jose de Moro and
other sites in Peru. “You can go up three meters and photograph a room, 300 meters and photograph a
site, or you can go up 3,000 meters and photograph the entire valley.”

Drones have flown over at least six archaeological sites in Peru in the past year, including the
colonial Andean town Machu Llacta some 13,123 feet above sea level.

Peru is well-known for its stunning 15th century Machu Picchu ruins, likely a getaway for Incan
royalty that the Spanish were unaware of during their conquest, and the Nazca Lines in southern
Peru, which are best seen from above and were mysteriously etched into the desert more than 1,500
years ago.

But archaeologists are just as excited about other chapters of Peru’s pre-Hispanic past, such as
coastal societies that used irrigation in arid valleys, the Wari empire that conquered the Andes
long before the Incas and ancient farmers who appear to have been domesticating crops as early as
10,000 years ago.